KR20100039345A - Handover between wireless cellular network and private network in wireless communications - Google Patents

Abstract

Techniques and systems for performing handover of a mobile station between a cellular wireless network and a private cell or private network.

Description

HANDOVER BETWEEN WIRELESS CELLULAR NETWORK AND PRIVATE NETWORK IN WIRELESS COMMUNICATIONS}

FIELD The present disclosure relates to wireless communication systems and techniques.

Wireless communication systems use electromagnetic waves to communicate with fixed and mobile wireless communication devices, such as mobile wireless telephones and laptop computers with wireless communication cards, which are located within the coverage area of the wireless communication system. Base stations are spatially distributed to provide wireless coverage in a geographic service area divided into radio cells. In operation, the base station transmits information to a wireless subscriber station (SS), such as a mobile station (MS), via a downlink (DL) radio signal generated at the BS. The MS in a particular cell sends information via its uplink (UL) radio signal to its serving base station for that particular cell. The base station may include a directional antenna to further divide each cell into different cell sectors where each antenna covers one sector. This cell sectorization increases communication capacity.

In some wireless communication networks, the base station may be configured in a multi-tier configuration. By way of example, a base station may be located in a radio cell of another base station to provide radio coverage of a small area of the radio cell. In such a case, the large cell may be considered a macrocell, since another base station is located in the macrocell area, and the smaller cell in the macrocell may be considered a microcell cell. Such a macro cell and micro cell configuration can increase the network's communication capacity by extending the wireless coverage of the network and increasing the radio frequency band. One macrocell may include one or more microcells depending on the need for wireless coverage in that macrocell. The base station configuration of this tier structure may further include picocells, each of which provides wireless coverage in a small area within the microcell.

The present application includes techniques and systems for performing handover of mobile stations between a cellular wireless network and a private cell or private network. In one implementation, a wireless communication system is a cellular wireless network comprising a plurality of cells with a base station to provide wireless access to a subscribed mobile station, the cellular wireless network comprising a list of neighboring cells for cells in the cellular wireless network. The cellular wireless network; A private wireless network comprising one or more private cells to provide wireless access to a subset of subscribing mobile stations in the cellular wireless network; A mechanism for obtaining mapping information between the serving cell in the cellular wireless network for the mobile station and the radio cells in the private wireless network to which the mobile station is authorized to access; And a mechanism for selecting radio cells in one or more private radio networks as candidate radio cells for handover of a mobile station from a serving cell in the cellular radio network to one of selected radio cells in the private radio network.

In another implementation, a wireless communication system is a cellular wireless network comprising a plurality of cells equipped with a base station to provide wireless access to a subscribed mobile station, the cellular wireless network comprising a list of neighboring cells for cells in the cellular wireless network. The cellular wireless network; A private wireless network comprising one or more private cells to provide wireless access to a subset of subscribing mobile stations in the cellular wireless network; A mechanism for obtaining mapping information between the serving cell in the cellular wireless network for the mobile station and the radio cells in the private wireless network to which the mobile station is authorized to access; A first handover mechanism for performing handover from a serving cell in the cellular wireless network to another cell in the cellular wireless network based on a list of neighboring cells for the cells in the cellular wireless network; And for access from a serving cell in the cellular wireless network to one or more private wireless networks authorized to the mobile station being served by the cell in the cellular wireless network from the serving cell in the cellular wireless network, without relying on a list of neighboring cells for the cells in the cellular wireless network. And a second handover mechanism for performing handover to a cell in the one or more private wireless networks based on the information.

In another implementation, a method for performing handover between a cellular wireless network and a private wireless network includes access to one or more private wireless networks that are subscribed to the cellular wireless network and authorized to mobile stations served by cells of the cellular wireless network. Providing information about the cellular wireless network. Each of the one or more private wireless networks provides wireless access to a subset of all users subscribed to the cellular wireless network. The method includes operating a cellular wireless network to obtain mapping information between a serving cell in the cellular wireless network and radio cells in one or more private wireless networks to which the mobile station is authorized to access; And selecting the radio cells in the one or more private radio networks as candidate radio cells for handover of the mobile station from the serving cell in the cellular radio network to one of the selected radio cells in the one or more private radio networks.

The above and other embodiments and features are described in more detail in the accompanying drawings and the description and claims.

A technology and system are provided for performing handover between a cellular wireless network and a private cell or private network.

1 illustrates an example of hierarchical cells in a wireless network deployment scenario.
2 illustrates an example flow of operations for handover from a macrocell to a private cell.

Apart from public wireless networks for providing mobile communication services to the public, various private wireless networks are becoming increasingly popular. Such private networks can provide wireless cells that cover selected service areas, such as homes, one or more offices, companies, and university campuses, and can provide wireless services in cooperation with public wireless networks. This collaboration of public and private networks can be used to provide the user with a high quality mobility environment within the zone in which the user wishes to remain in communication while on the move. Handover between small localized cells of a macro-cellular network and a private wireless network is needed to provide continuous communication for users using both the macro-cellular network and the private wireless network. The wireless coverage configuration that needs to be considered for this type of handover may be different from that of a conventional wireless network. Instead of cells configured primarily to provide wireless coverage to adjacent areas, nowadays many potentially small cells are within the coverage area of the macrocell. In addition, access to lower small cells and networks is generally limited to a small subset of users of a macrocellular network.

In the example below, a cell represents a wireless coverage area that may require handover to maintain communication continuity as the mobile station moves into the wireless coverage area. For example, a cell may comprise sectors of an omnicell or sectorized cell in real world placement and operation and processing by a cell performed by a base station associated with that cell. A macrocell is a cell in a wireless network that has the privileges and privileges that all members of the users of the wireless network have access to. In the following example, a private cell or private network has limited access rights to only selected users and such private cell or private network includes a femtocell and a home wireless access point. Such a private cell or private network has different characteristics from a conventional wireless network. Therefore, in private cells and private networks such as home zones, office areas, and campus cells or networks, a technique for supporting handover from one cell to another cell used in a micro cell network is a handover between a macrocell network and a private network. It can be inefficient in dealing with.

As an example, one feature of some conventional handover mechanisms that do not adapt well to supporting handover between a macrocell network and a private network uses a neighbor cell list that is believed to be generally applicable to all users in the coverage area. It is. More specifically, there may be a potentially very large number of lower cells and the neighbor list, which may be applied to the upper macrocells, may be a large list and this large to help the mobile station determine a potential target cell. Broadcasting a neighbor list can consume a significant amount of transmit and receive capacity over the air. In particular, the lower cell may tolerate a small subset of users and prohibit access by other users, and the MS may determine which neighbors that are not applicable are received and processed and applicable to the MS for handover. Since there is no mechanism for the MS, including and advertising all cells in the generic neighbor list makes it inefficient to determine the target cell for handover by all mobile stations.

In another example, various macrocell mobile networks use automatic MS scanning to determine the candidate cell that is most likely for handover. Cells in the list can only tolerate a small subset of users and prohibit access by other users, so if the MS is not provided with information about the cell's accessibility and subset membership, the MS will successfully access the MS. It is forced to evaluate and suggest potential handover target cells that are not authorized to do so.

The present application describes examples and implementations of techniques and network designs that provide efficient handover between macrocell networks and private networks. In general, the overall system interaction between a private cell / network and a macrocell network described herein also applies between a private cell / network and a pico or micro cell network. Thus, whenever reference is made to the macrocells described herein, the content also applies to pico cells and micro cells.

1 illustrates an example of a hierarchical cell in a wireless network deployment scenario. Multiple macrocells are provided in the service coverage area for access by all subscribed users. Also illustrated are micro cells and pico cells that can be accessed by all subscribed users. The private cells and networks of FIG. 1 are different from macrocells, microcells, and picocells and are private cells and networks in that only a subset of users subscribed to the macro-cellular network are accessible. Because access is restricted, control over which users can be allowed to access private cells and networks is managed separately from subscriptions for access to the macrocellular network. In one implementation, by way of example, access control in a subcell or network is a right for a user device to access the subcell or network based on a distinguishable identifier, such as a MAC address in a protocol message sent by the user device. Can be done using an access control list (ACL) to determine. In other implementations, the access control can be done with full authentication and authorization for both the user and the device.

In the example described herein, it is assumed that the management relationship between the lower private cell or network and the macro-cellular network includes the following features. First, there is business coordination, whereby a user accessing a private subcell or network may not be able to provide wireless access if the service cannot be provided from the private cell or network (that is, move out of the coverage area of the subcell or network). In order to join the macro-cellular network. One example of this type of relationship is that lower private cells or networks and macro-cellular networks can be operated by the same business entity. Second, any user additions authorized to access the lower private cell or network are known to communicate to the management system of the macro-cellular network and to an identifier by which the user can be associated with users and devices authenticated by the macro-cellular network. There is a trust relationship between the management entity of the underlying private cell or network and the macro-cellular network that can be identified by. Third, the macro-cellular network has knowledge of the geographic location and coverage area of lower private cells and networks. With this knowledge, a macro-cellular network can map the location of a private cell or the location of one or more border cells of a private network to the coverage area of a macrocell of a macrocell cellular network.

The handover technique of the present invention uses a potential mechanism using other mechanisms to provide an efficient, effective and fast decision on a private cell or network as a potential handover while the MS is served by each higher macrocell of the macrocell cellular network. It can be used to augment and supplement existing mechanisms for automatic MS scanning and neighbor lists for handover targets. In a macrocell, the neighbor list is maintained for another neighboring macro-cell but no neighbor list entry is added for the lower private cell or one of the private wireless networks to be considered to be the boundary cell between the private network and the macro-cell network. No addition is made for more cells. In particular, relevant operational information for each MS being served is maintained in the serving macro-cell to facilitate efficient, effective and quick decisions for the subcells as potential handover targets in the private cell or network.

The above relevant operational information for each mobile station maintained in the serving macro-cell includes the identity information of the lower private cell in the coverage area of the macro-cell that the user of the MS has permission to access. Using this information, the macro-cell may use network initiated scanning to instruct the MS to measure and report on the identified lower private cell to which the MS has permission to access. Based on this measurement report, the macro-cell may determine when to instruct the MS to perform handover to an authorized lower private cell based on the handover policy. One example of such a policy is to always force handover to the allowed subcells while the evaluated service is deemed acceptable in the allowed subcells. Another policy may be to use the above policy as a modified baseline policy, except that the speed of the MS is determined to be greater than a certain threshold, such as, for example, 10 miles per hour. There may be a number of modified policies and fit into this decision framework. The MS may be operated based on existing mechanisms defined by other methods or techniques, such as indication by manual operation by the user, and the MS may initiate to perform a handover to an allowed subcell. The macrocell network may leverage the operational information described above to assist the MS in determining the appropriate handoff target cell. By way of example, a user may execute a command of an MS device that presses a key or otherwise forces a handover from a macrocell to a private cell. In another example, the MS detects that a certain handover decision threshold has been reached and then initiates a handover to a potential target private cell.

In one implementation, the handover mechanism can be implemented to include the following aspects. First, the Macro-Cellular Network recognizes and acquires the information to keep the user MS for future use of information that the user has been granted access to the lower private cell or network, and the internal elements of the Macrocell to immediately use this information. Distribute as needed. Second, a mechanism is provided for determining the lower private cell applicable to each user MS being served by the macrocell. Third, a mechanism is provided for obtaining measurements for these cells for evaluation of potential handover target private cells without having to include in the neighbor cell list the lower private cells applicable to the user MS.

An example is now described for macrocells obtaining information about private cell membership. It is assumed that the lower private cell / network is set by default to not allow any end user to access its network, and some method is local to the lower private cell / network to provide access privileges for new users and devices. It is assumed to be provided. As one example for implementing this method, an access control list (ACL) may be provided whereby a MAC address or other unique identifier type of a wireless communication device associated with an authenticated user is entered. As another example of implementing this method, secure private information associated with each authenticated user that is compatible with the security authentication and authorization protocols supported by the wireless technology is managed, authenticated and authenticated (AAA). Authorization) can be entered into the database.

Under existing trust relationships existing between the management entity of the lower private cell / network and the macro-cellular network, whenever a user is granted access to the private cell / network provided as an access privilege, the private cell / network is assigned to the user identifier. To a particular private cell / network (as identified by an authorized identifier for a cell or network identifier) by a particular user, such as identified by an authorized identifier for the device (this may be an identifier of a device associated with the user) Provide such information to the macro-cellular network associating a permission for access. This information exchange can occur through various means. For example, such information exchange may be private to private communication. As another example, this information exchange can occur automatically by signaling a protocol between the private cell / network and the macro-cellular network.

In operation, the macro-cellular network is kept up to date with respect to the current list of each user authorized to access a particular private cell / network. With such information and knowledge about the particular sub-private cell or coverage area and geographic location of the macro-cellular network, the macro-cellular network is a user and hand from the macro-cellular network to the sub-private cell / network. It can be operated to associate with specific macrocells within a particular macrocell network that may be involved in oversight and with a particular private cell or border cell of the private network.

In response to a change to the list of users authorized to access a private cell / network, the macrocell network may generate one entry for a user newly granted access to the private cell or network, the macro-cellular network associated with that user. Included in the action data, this entry may contain a macrocell, if any, for the macrocell for which the user may perform handover to the private cell, or a macrocell ID for the macrocell for which the user may perform handover from the private cell, and It includes a private cell ID for each or a private cell of one or more border cells in the private network. If there is no macrocell suitable for performing a handover with a private cell or private network, the entry for the macrocell ID may be set to zero to indicate that the mobility service cannot be provided from the macro-cellular network to a specific private cell. have. In this case, nomadic service may be provided to the user.

Any new private cell entries, such as the private cell entry described above, are incorporated into the user's macro-cellular subscriber operation information. In one implementation, this information can be maintained as part of subscriber profile information and a full set of private cell ID information (along with other necessary configuration and operational information associated with the user) each time a user is successfully authenticated for the service. It can be stored in the home AAA function (H-AAA function) to be enabled. If the user is already active in the macro-cellular network and the macro-cell the user is currently serving is one of the cells where the handover can be done as a private cell, the new private cell ID is the potential private cell handover for the user. To the serving macro-cell to be added. This information may be added to handover context information to be transmitted to the target cell when the target is a macro-cell.

When a user is served by a macro-cell, various mechanisms may be provided for the macro-cell to obtain private cell information applicable for the user. In one example of such a mechanism, the macro-cell queries a more centralized location / function for any such information about the user. Such a more centralized location / functionality part may be the H-AAA itself or a private cell gateway that allows the local agent of a private cell in the current serving access network to provide such information to support handoff operation for the appropriate user. have.

In another example of such a mechanism, when entering a macro-cell with a handover, the entire set of private cell IDs and associated macro-cells are associated with the macro-cell as part of the handoff context from the previous serving macro-cell. Can be sent to. From the data received by the macro-cell, the macro-cell may determine whether the user has any private cells within the coverage area of the macro-cell to which the user has access privileges. The H-AAA or private cell gateway may be operable to put access privilege information into the local agent of the private cell in the access network. This behavior helps ensure that the handoff context is up to date because new users can add and delete new users to access the private cell / network while the user is currently active in relation to the serving access network. Can be used. As a result, the handoff context of that user is updated by having access privileges to the private cell.

Based on the updated information for the private cell or private network, a handover target may be selected from the private cell or network identified in the private cell mapping for handover from the macro cell to the private cell. Based on the information acquisition, processing, and dissemination processes described herein, a macrocell is a cell that is currently being served by a macrocell that provides access to one or more private cells as a cell to which the macrocell can support handover. I know I have it. One example is for a procedure between a macrocell and a user's MS to make such a private cell a potential handover target without the necessary support by the list of advertised neighboring cells.

2 illustrates the operational flow in this procedure.

1. The user MS initiates a wireless service from the access network via the macrocell. This may include 1) handover from another macro cell or from a lower private cell, 2) reentry or reactivate into the network from an MS idle state, or 3) when the MS first attempted access or if the MS was already deactivated ( The MS may be powered down and deactivated), which may occur in several ways, including after being activated.

2. Upon completion of the network entry or reentry procedure, the macrocell obtains handoff context information regarding the user's access privileges to all private cells to which the macrocell can support handover. There are many ways to obtain this information and in certain implementations one may choose to use one or more of the above methods based on considerations such as system performance, cost and complexity.

3. If the Private_Cell_Scan_List for the user is empty, the MS is instructed by the macrocell to report the initial measurement set for each private cell in the list using the target cell scanning procedure initiated by the network provided by the wireless technology. These measurements help to assess the relative probability that one of the private cells is more likely to be a handover target than others. Such measurements may include, for example, Received Signal Strength Indication (RSSI) and Carrier to Interference and Noise Ratio (CINR).

Alternatively, Private_Cell_Scan_List may be used to build a set of private neighbor cell information provided in the MS. Each MS with access privileges to one or more private cells / networks may have unique private neighbor cell information that is different from the universal macrocell neighbor list and not available to other MSs. The information contained in each entry of the private cell neighbor list is used to perform scanning (carrier frequency and base cell identification) and for target handover selection (signal quality threshold), and fast handover (critical physical and MAC layer communication parameters). Information in a generic macrocell to provide sufficient information to the MS to support the < RTI ID = 0.0 > After the mobile station initiates scanning of the private cells in the list, the mobile station uses a different private cell to process the measurement of signal quality and selects one or more candidate cells for the handover target private cell. The mobile station then communicates the selected one or more candidate cells to the base station of the macrocell, which then evaluates this information to make a final selection for the target private cell for handover.

In addition, the private cell neighbor information may include information about a handover / cell selection policy such as a priority for the selection of a private cell versus another private cell or a private cell versus macrocell. The MS uses this private cell neighbor information to augment the general macrocell neighbor information that it typically receives as broadcast information from the macrocell. This private cell neighbor information may be provided statistically or quasi-statistically to the MS if information is provided on all private cells to which the MS has access privileges, in which case the information may be lost or obtained by the MS. Can only be changed if or only when any private cell neighbor information is changed.

Private cell neighbor information may be maintained dynamically only if a subset of private cell neighbor information is provided to the MS at any point in time, such that a subset of private cell neighbors is within the coverage area of the group of one or more macrocells. This corresponds to the scenario where Private_Cell_Support_Zones is defined. This dynamic update may occur via signaling from a macrocell to the MS when the MS obtains a service from a particular macrocell either through a handover to a particular macrocell or through or entering or reentering a network through the handover, Such signaling is necessary only if the MS does not yet have a suitable set of private cell neighbor information, the suitability of the private cell neighbor information set may be identified by a code (eg, Private_Cell_Support_Zone_ID). If private cell neighbor information is provided in the MS, this information can be scanned for the private cell neighbors without reporting explicitly by the macrocell and can report the scanned measurement results or based on the universal macrocell neighbor list. A handover candidate cell for the macrocell may be proposed based on a specific configuration of private cell neighbor information similar to its own operation.

4. The MS may perform the requested measurements if the MS is not busy to support communication active for the user. If all requested measurements have been completed or if the requested intermediate results are available, such measurements are reported to the macrocell at least once.

5. The macrocell processes the measurement results and if it is apparent that it is a potential handover target, determines the scanning requirements for each private cell in the Private_Cell_Scan_List according to its relative potential as a potential handover target. If not obvious, the scanning set point can be set equal for all private cells.

6. After collecting enough measurements to obtain confidence in the validity and stability of the radio link between the private cell and the network on the list, and in a handover hold period that may be effective to prevent excessive handover ping-pong operation. If does not belong, the macrocell evaluates the results for all private cells in the Private_Cell_Scan_List to determine if any target meets the configured handover target selection criteria, eg, RSSI greater than RSSI_Threshold and CINR greater than CINR_Threshold. do. If the MS is in the handover hold period, the first evaluation occurs at the expiration of this hold period.

7. If more than one private cell meets each individual target selection criterion, the private cell that should provide the best service may be selected as a handover candidate cell which may be the private cell for which the best CINR is to be measured. Handover target selection may also be adjusted by criteria based on a policy such as selecting a private cell designated as a home private cell having priority in the selection versus a private cell not based on this designation.

8. Handover from the Serving Macro Cell to the Target Private Cell The handover may be performed based on the handover initiated in the network as defined by the wireless technology.

The above handover process for the MS handing over from a macrocell to a private cell or network may be based on a handover process initiated in the network. Alternatively, the MS may leverage the information and procedures collected as described above to perform the handover procedure initiated at the MS towards the target private cell.

In the above example for the handover process, the serving macrocell may obtain handoff context information regarding user access privileges to access private cells and networks through various techniques. Several examples are described below.

In one example where a user MS has started serving at a serving macrocell as a result of handover completion, the entire mapping set of macrocells may be transmitted from the previous serving macrocell to the current serving macrocell as handoff context information of the MS. . This information can support the MS's handover decision to each private cell that is neighboring the current serving BS and the user of the corresponding MS has access privileges to the base station of the new target private cell to which the MS can hand over. The current serving macrocell processes the list of private cell to macrocell mapping information and determines which private cell among the private cells that are neighbors of the current serving macrocell, if any, the user and the MS potentially have a handover. Can be done. In addition, the list of potential private cells for which the MS has access privileges may be prioritized to optimize the network initiated scanning and / or network initiated handover decisions. Without a suitable single private cell or network, the handover target selection procedure specific to that private cell is invalid (ie, exited from this procedure). If there is at least one suitable target private cell or network, the identity information of these private cells is inserted into a new list, Private_Cell_Scan_List, as a possible private cell handover target. If these private cells were prioritized, the list would be organized according to the assigned priorities.

The procedure involves too many private cell entries that can cause the MS's handover context to be too large if information about all of these private cells is included (i.e. the user is allowed access to many private cells). Macrocells are organized into a subset called Private_Cell_Support_Zones identified by Private_Cell_Support_Zone_ID. Each macrocell is assigned to a specific Private_Cell_Support_Zone for a given user and therefore has a Private_Cell_Support_Zone_ID associated with it.

Some preprocessing for the entire set of private cell to macrocell mapping information for the user and the MS is based on partitioning all macrocells in the macro-cellular network into reasonable Private_Cell_Support_Zones for a given user. It is done within a macro-cellular network to divide the entire set of macrocell mapping information into a small, reasonable number of subsets. A subset of these mapping data can be cached at any location in the macro-cellular network and an individual macrocell from the macro-cellular network can query about a subset belonging to a particular Private_Cell_Support_Zone.

During the handover execution operation, if Private_Cell_Support_Zone_ID is assigned, this Private_Cell_Support_Zone_ID is provided by the potential target cell for the current serving macrocell during preparation of the handover preparation procedure. If the handover target belongs to the same Private_Cell_Support_Zone_ID as determined by having the same Private_Cell_Support_Zone_ID assigned, then the current serving macrocell contains a subset of its own private cell to macrocell mapping information and uses this subset as the MS's handover context. Passed to the target macrocell as part of the information and the procedure can be completed based on what has been described above. If the handover target does not belong to the same Private_Cell_Support_Zone_ID as the handover target as determined by having a different Private_Cell_Support_Zone_ID assigned, then the current serving macrocell does not contain any private cell to macrocell mapping information and thus upon completion of the handover, The procedure proceeds as described below.

After the user MS completes network entry or reentry, if the macrocell does not contain any private cell to macrocell mapping information, then the macrocell obtains mapping information from a more centralized location / function within the macrocell network. Continue the operation. In this type of scenario, the procedure can continue in various ways. Two examples are described below.

In the first example, the procedure implementation is more centralized even when the macrocell completes the handover, meaning that the private cell to macrocell mapping information is never included in the handover context information. In this case, the following two alternative procedures or other procedures may be applied.

In the first procedure, some processing is done at a more centralized location / function or the preprocessing is performed so that only the list of private cells to which the user has access privileges and the macrocell can support handover is provided to the macrocell. Is done in. If no private cell is provided to the macrocell in response to a query from the macrocell to a more centralized location / function, then the remainder of this private cell-specific handover target selection procedure is invalid (ie Escaped Caesar). If more than one private cell is provided, the identity information of these private cells is inserted into a new list, Private_Cell_Scan_List, as likely private cell handover targets.

In the second procedure, a full set of private cell to macrocell mapping information for a user is provided to the macrocell, and the macrocell itself uses a subset of private cells for which the user has access privileges and the macrocell can support handover. Handle for it and maintain it. Processing for the entire set of private cell to macrocell mapping information may be performed as described above.

In a second example, several mechanisms may be provided if the procedure implementation intends to include private cell to macrocell mapping information as part of the handover context information. In one example, if no Private_Cell_Support_Zone_ID is assigned to the macrocell, then the full set of private cell-to-macrocell mapping information for the user is obtained from a more centralized location / function and as part of the MS's handover context information (to the macrocell). Or a more centralized location / function). In another example, if a MacroCell is assigned a Private_Cell_Support_Zone_ID, only a subset of the private cell to macrocell mapping information for the user in Private_Cell_Support_Zone is obtained from the location / function that is more centralized by the MacroCell and the hand of the MS Held as part of the over context information (in a macrocell or in a more centralized location / function).

The user MS served by the private cell or network may be handed over through a macrocell or other cell in the macrocell cellular network. As part of this handover, information about neighboring macrocells of the serving private cell may be obtained. In one embodiment, the set of macrocells that are potential handover targets in a particular private cell is the first time that the private cell registers the user as a cell with allowed access or when the potential macrocell handover target candidate is changed ( For example, perhaps due to some wireless coverage of the macro cellular network in proximity), it may sometimes be provided to a particular private cell by the macro-cellular network as needed. As such, the private cell evaluates the neighboring cell to find suitability as a handover target and, if the appropriate conditions are met, the neighbor list of handover target candidates used in the conventional manner to trigger one of the macrocell targets. Use this information to build.

Based on the neighbor list, the handover target selection process may follow a process driven by the MS, such as scanning initiated by the MS, to select a macrocell for handing over the MS. As an example, the macrocell-to-macrocell handover procedure disclosed by the MS is a policy versus best service that biases the service to a private cell if the quality of the parameters of the handover target selection criteria can be tolerated. It may be used where it is chosen to tailor the handover to fit some policy-based behavior, such as policies using quality conditions.

The above examples illustrate a number of features for effectively handling handover between a macrocell network and a private network. These features share a list of valid users between the macrocell network and the private cell network to provide mapping between the macrocell and the corresponding neighbor cell, and support dynamic updating of the mapping between the macrocell and the corresponding neighbor private cell. To do; Adding new private cell to macrocell mapping information to subscriber information; Using the macrocell to provide mapping information to the macrocell and determine a private cell for a user that can apply to the macrocell; Using private cell scanning and private cell to macrocell mapping information initiated by the network for the private cell to determine suitability as a handover target, thereby eliminating the need to add the private cell to the list of advertised neighboring cells; And processing the measurements and applying any policy criteria as part of the handover target selection. Various techniques for providing mapping information to a macrocell include sending the macrocell query to a more centralized location / function unit having a private cell valid for the user and applicable to the macrocell; Operating a macrocell to extract a private cell in the list applicable to the macrocell from all private cell to macrocell mapping information; Providing a full set of private cell to macrocell mapping information as part of handover context information from a previous serving macrocell; It may be used in various implementations, including providing a defined subset of private cell to macrocell mapping information, such as divided into Private_Cell_Support_Zone and transmitted from the previous serving macrocell as part of the handover context information.

A handover technique for handover between a private cell and a macrocell may be implemented to be compatible with a handover process between different macrocells. For example, one example of a wireless communication system that currently implements a handover technique is a cellular wireless network that includes a plurality of cells having a base station to provide wireless access to subscribed mobile stations and is a neighbor to a cell in the cellular wireless network. A cellular wireless network comprising a list of cells; A private wireless network comprising one or more private cells to provide wireless access to a subset of subscribing mobile stations in the cellular wireless network; A mechanism for obtaining mapping information between a radio cell in a private radio network to which the mobile station is authorized to access and a serving cell in a cellular radio network for the mobile station; And a first handover mechanism for performing handover from a serving cell in the cellular wireless network to another cell in the cellular wireless network based on the list of neighbor cells for the cell in the cellular wireless network; A serving cell in a cellular wireless network based on information about access to one or more private wireless networks allowed by the mobile station being served by the cellular wireless network, rather than based on a list of neighboring cells for the cells in the cellular wireless network. And a second handover mechanism for performing handover from the cell to the cell in the cellular wireless network.

Although this disclosure contains many specific details, these should not be construed as limiting the scope of the invention as claimed or claimed, but rather as being characteristic to a particular embodiment. . These features described herein in the context of separate embodiments can be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can be implemented individually or in any suitable subcombination in multiple embodiments. Moreover, even if the features are described as functioning in a consistent combination and may be initially claimed as such, one or more features from the claimed combination may in some cases be deleted from this combination, and the claimed combination May relate to a subcombination or to variations of this subcombination. Likewise, although the operations have been described in a particular order in the drawings, in order to achieve the desired results, this description requires that such operations be performed in the order specifically illustrated or sequentially, or that all of the illustrated operations are performed. It should not be understood as

Only a few embodiments and implementations have been described. Modifications, modifications and improvements to the embodiments and implementations described above can be made based on those disclosed in other embodiments.

Claims (21)

A method for handling handover between a cellular wireless network and a private wireless network, the method comprising:
Provide the cellular wireless network with information about access to one or more private wireless networks that are subscribed to a cellular wireless network and being served by a cell of the cellular wireless network, each of the one or more private wireless networks; Provide wireless access for a subset of all users subscribed to the cellular wireless network;
Operate the cellular radio network to obtain mapping information between radio cells in the one or more private radio networks to which the mobile station is authorized to access and serving cell in the cellular radio network;
Selecting radio cells in the one or more private radio networks as candidate radio cells for the mobile station to handover from the serving cell in the cellular radio network to one of the selected radio cells in the one or more private radio networks; To do
A method for processing handover between a cellular wireless network and a private wireless network. The method of claim 1,
Apply a selection condition for selecting one radio cell from the candidate radio cells as a target radio cell for the handover;
Performing a handover of the mobile station from the cellular radio network to the selected one target radio cell
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 2,
Measuring signal quality of a radio link between the mobile station and wireless cells in the one or more private wireless networks that the mobile station has access to and adjacent to the serving cell of the cellular wireless network;
Selecting the candidate radiocells for handover of the mobile station using the measured signal quality
A handover processing method between a cellular wireless network and a private wireless network comprising a. 4. The cellular wireless network and private network of claim 3, wherein the received signal strength and carrier to interference and noise ratio are measured to indicate signal quality of a radio link between the mobile station and the mobile station in the one or more private wireless networks. How to handle handover between wireless networks. 2. The method of claim 1, wherein the information about access to one or more private wireless networks authorized by the mobile station being served by a cell of the cellular wireless network is neighbors of the serving cell to the mobile station in the cellular wireless network. And a list of cells in the one or more private wireless networks. The method of claim 5,
A list of cells in the one or more private wireless networks that are neighbors of the serving cell for the mobile station in the cellular wireless network is previously moved from the previous serving cell in the cellular wireless network to the serving cell currently serving the mobile station. Providing as part of a handover context information package for the mobile station to handover to
A handover processing method between a cellular wireless network and a private wireless network comprising a. 6. The method of claim 5, further comprising: operating the serving cell to obtain a list of cells in the one or more private wireless networks that are neighbors of the serving cell for the mobile station in the cellular wireless network from another entity in the cellular wireless network. A method of handling handover between an cellular cellular network and a private wireless network. The method of claim 5,
Accessing a base station of the serving cell to obtain a list of cells in the one or more private wireless networks that are neighbors of the serving cell for the mobile station in the cellular wireless network from another entity in the cellular wireless network
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 8,
If the base station of the serving cell does not have any entry in the list of cells in the one or more private wireless networks that are neighbors of the serving cell for the mobile station in the cellular wireless network, within the cellular wireless network for the list. Accessing other entities
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 1,
Storing in the mobile station a list of cells in the one or more private wireless networks that are neighbors of the serving cell to the mobile station in the cellular wireless network.
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 10,
The mobile station to initiate scanning of cells on the list of cells in the one or more private wireless networks that are neighbors of the serving cell to the mobile station in the cellular wireless network to determine the signal quality of the radio link with the cells in the list Operating
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 11,
Operating the mobile station to evaluate a measure of signal quality of the radio link with cells on the list and to select one or more candidates for a target radio cell in the list for the handover
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 12,
Operating the mobile station to communicate by communicating the selected one or more candidate cells for the target radio cell in the list for the handover to the serving cell in the cellular radio network.
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 10,
Storing a handover policy in the mobile station
A handover processing method between a cellular wireless network and a private wireless network comprising a. The method of claim 1,
The cellular radio list of neighboring cells for cells in the cellular radio network that is distinct from information about access to one or more private radio networks authorized by the mobile station being served by a cell of the cellular radio network at the mobile station. Providing to the network;
Perform a handover from the serving cell in the cellular wireless network to another cell in the cellular wireless network based on the list of neighboring cells for cells in the cellular wireless network;
Not based on the list of neighboring cells for cells in the cellular wireless network, and in the information regarding access to one or more private wireless networks authorized by the mobile station being served by a cell of the cellular wireless network; Performing handover from the serving cell in the cellular wireless networks based on a cell in the one or more private wireless networks
A handover processing method between a cellular wireless network and a private wireless network comprising a. In a wireless communication system,
11. A cellular wireless network comprising a plurality of cells with a base station to provide wireless access to subscribed mobile stations, the cellular wireless network comprising a list of neighboring cells for cells in the cellular wireless network;
A private wireless network comprising one or more private cells to provide wireless access to the subset of subscribing mobile stations in the cellular wireless network;
A mechanism for obtaining mapping information between a serving cell in the cellular wireless network for a mobile station and radio cells in the private wireless network to which the mobile station is authorized to access;
A first handover mechanism for performing a handover from the serving cell in the cellular wireless network to another cell in the cellular wireless network based on the list of neighbor cells for cells in the cellular wireless network; And
Without information based on the list of neighboring cells for cells in the cellular wireless network, the mobile station in the information about access to one or more private wireless networks authorized to the mobile station being served by a cell of the cellular wireless network A second handover mechanism for performing handover based on the serving cell in the cellular wireless network to a cell in the one or more private wireless networks based on the
To include, a wireless communication system. The method of claim 16,
A mechanism for selecting radio cells in the one or more private radio networks as candidate radio cells for the mobile station to handover from the serving cell in the cellular radio network to one of the selected radio cells of the one or more private radio networks;
A mechanism for applying a selection condition for selecting one radio cell as a target radio cell for the handover from the candidate radio cells; And
Mechanism for performing handover of the mobile station from the cellular radio network to the selected one target radio cell
To include, a wireless communication system. In a wireless communication system,
10. A cellular wireless network comprising a plurality of cells with base stations to provide wireless access to subscribed mobile stations, the cellular wireless network comprising a list of neighboring cells for cells in the cellular wireless network;
A private wireless network comprising one or more private cells to provide wireless access to the subset of subscribing mobile stations in the cellular wireless network;
A mechanism for obtaining mapping information between a serving cell in a cellular wireless network for the mobile station and radio cells in the private wireless network to which the mobile station is authorized to access; And
A mechanism for selecting radio cells in the one or more private radio networks as candidate radio cells for the mobile station to handover from the serving cell in the cellular radio network to one of the selected radio cells in one or more private radio networks
To include, a wireless communication system. The method of claim 18,
A mechanism for applying a selection condition for selecting one radio cell from the candidate radio cells as a target radio cell for the handover; And
A mechanism for performing a handover of the mobile station from the cellular radio network to the selected one target radio cell
Including, a wireless communication system. 20. The mobile station of claim 19, wherein the information about access to the one or more private wireless networks granted to the mobile station being served by a cell of the cellular wireless network is neighbors of the serving cell to the mobile station in the cellular wireless network. A list of cells in the one or more private wireless networks. 20. The system of claim 19 wherein the cellular wireless network comprises at least one of macrocells and a microcell located within the macrocell or a picocell located within the macrocell.

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